It makes an unfortunate amount of sense that a movie about snails would start slowly.

Thankfully, “Turbo” picks up speed right around the same time its star does. Though it skews a little too grown-up to qualify as a great kids’ movie, Dreamworks’ tale of a super-fast snail ends up being sweet, offbeat and surprisingly funny. Like any good racer, the movie saves all its energy for the home stretch.

Unfortunately, you have to make it through the first 20 or so minutes before the engines start revving. “Turbo” sets its “Don’t give up on your dreams” message firmly in the adult world, giving the snails a 9-to-5 factory-style job harvesting tomatoes for themselves. Theo, voiced by Ryan Reynolds, hates his job, is obsessed with the Indy 500, and wants nothing more than to go very, very fast.

Everyone else tells him to stop being an idiot and accept reality, a scenario that will be far more familiar to a 30-year-old who missed out on his dreams of playing in a band than a six-year-old who still wants to be an astronaut. A sequence with a lawn mower that really drives the point home is particularly hard to watch.

Then fast cars and ludicrous science gets involved, and the movie rediscovers its sense of fun. The jokes get funnier and far more frequent, always just offbeat enough to feel fresh. Reynolds really shone here, his dry delivery perfect for the movie’s brand of humor.

The “racing snails” also add to the movie’s imagination and sense of liveliness. Even if you don’t recognize all of the actors/musicians doing guest voices, their race along the power lines is a pure shot of fun that made me envious I wasn’t somehow involved. Even better are their schemes to help get Theo to the Indy 500, precision teamwork that wouldn’t have been out of place in a live action heist movie.

The supporting cast is equally fun. Michael Peña adds a hefty dose of sweetness to the movie as Tito, a human who has the same kind of dreams as Theo the snail. Ken Jeong is wildly stereotypical, hilarious, and just a little terrifying as Kim-Ly, one of the humans who becomes involved with Theo’s pit crew. Bill Hader utterly transforms his voice to play Guy Gagne, a racecar driver whose warm bluster hides a sharp-edged and potentially dangerous arrogance. Samuel L. Jackson essentially plays himself in snail form, and in the process ups the movie’s coolness factor by at least 20 percent.

By the time Leo’s in the last few laps of the race, the movie’s put you in a good enough mood that you’ll be cheering him on just as much as the people in the audience. Sure, the movie makes no sense, but for a second it seems entirely possible that a little snail could win the Indy 500. And more importantly, that he deserves to win.

After all, the little guy may have started slow. But it’s the end that everyone remembers.